The Hematology Research Training Program at the University of Pennsylvania was established in 1978 and has provided training for 111 basic, translation and patient-oriented investigators. Since 2004 the program and this T32 have supported 8 postdoctoral and 4 predoctoral trainees per year. The continuing goal of the program is to help individuals interested in the broadly-defined disciplines of hematology prepare for careers as independent investigators. Originally the candidates were drawn almost exclusively from physicians enrolled in the clinical hematology training programs in the Departments of Medicine and Pediatrics. Since 1998 we have included non-physician postdoctoral trainees and since 2004 we have also incorporated predoctoral trainees, with an emphasis on future physician-scientists in Penn's MD-PhD program to take advantage of the Pi's role as the director of that program. The addition of predoctoral MD-PhD and PhD students to the program reflects our belief in the long term value of attracting talented students in hematology-related research at an earlier point in their training as scientists and physician-scientists. Starting in 2006, PhD candidates at Penn, including those in this program, have also had the option of enrolling in the Graduate Training in Medical Sciences (GTMS) Certificate Program, expanding their opportunities for cross training in human biology and disease. Outcomes. During the first 29 years of funding, 103 postdoctoral trainees (66 MD, 13 MD-PhD and 24 PhD) and 8 pre-doctoral trainee (6 MD-PhD and 2 PhD) have been supported. Of the 90 postdoctoral trainees who have completed training, 61% hold full-time appointments at an academic institution and are engaged in either laboratory or clinical research. An additional 9% are engaged primarily in clinical practice, but have university appointments and participate in clinical research projects and teaching part-time. 53% of our former trainees who have completed training have extramural research funding from the NIH and other sources, 11% have positions in industry and 4% are completing further postdoctoral studies. A detailed plan for identifying appropriate predoctoral and postdoctoral candidates, providing them with the skills needed for an independent career, and mentoring them throughout the process is included in the application.